The subject application relates to image defect correction in a printing system. While the systems and methods described herein relate to compensating or correcting defects in a scanned or electronic image or document, it will be appreciated that the described techniques may find application in other printing systems, other xerographic applications, and/or other scanning systems.
When a hard copy of a document is scanned to generate an electronic copy thereof, artifacts can arise that degrade the quality of the electronic document. For instance, punch holes that have been punched in the margin of the document may appear as dark spots on the electronic document. Another type of artifact is “show-through,” which occurs when images or text from the back side of the scanned page show through to the side being scanned. Yet another type of artifact involves show-through of a roller applied to the back of the scanned page.
Attempts to mitigate image show-through artifacts have included using a dark backing behind the scanned page. However, this technique makes punch holes appear darker. Attempts to mitigate roller show-through artifacts have included darkening the roller, but again this technique exacerbates punch hole artifacts because the darker roller shows through the punch holes more than a lighter roller would.
Other attempts at mitigating roller show-through have included placing a pattern on the roller, and employing software that detects the pattern where it shows through the punch holes and digitally corrects or removes the image of the punch hole. However, this technique is expensive and cost-prohibitive.
Less-expensive punch hole correction techniques include blanking out the entire length of the margin of the scanned page in which the punch holes are located. However, this technique is coarse and results in loss of information (e.g., hand-written notes, text, images, etc.) included in the blanked margin region.
Accordingly, there is an unmet need for systems and/or methods that facilitate removing punch holes in a scanned document image while overcoming the aforementioned deficiencies.